Electrical connectors are known which have a plurality of terminals disposed in a dielectric housing and which are to be terminated to a respective plurality of conductor wires, and the housing then secured within a protective shell. In one such connector the terminals are disposed in a single row within a wafer-like dielectric housing or module and extend rearwardly from the housing, to conclude in termination sections comprising shallow channels termed solder tails. The housing may include cylindrical portions extending rearwardly to surround the terminals forwardly of the solder tails. When the conductor wires are prepared to be terminated to the solder tails, individual sleeve-like solder preforms encased within respective longer sleeves of heat recoverable or heat shrink tubing are placed over the rearwardly extending terminal portions so that the solder preforms surround the solder tails, or a strip of such units appropriately spaced apart; the stripped wire ends are then inserted into the heat recoverable tubing sleeves and into the solder preforms surrounding the solder tails. The connector assembly is then heated to an elevated temperature such as by being placed in a conventional convection oven or by a stream of hot air directed at the tubing sleeves.
The heat energy penetrates through the heat recoverable tubing to melt the solder which then flows around the stripped wire ends within the solder tails and upon cooling forms respective solder joints joining the conductor wires to the terminals; and simultaneously the heat recoverable tubing is heated above a threshold temperature at which the tubing shrinks in diameter until it lies adjacent and tightly against surfaces of the solder tails and the wire termination therewithin, against a portion of the insulated conductor wire extending rearwardly therefrom, and against a portion of the terminal extending forwardly therefrom to the rearward housing surface covering the exposed metal surfaces. Apparatus for wire and sleeve handling with respect to such a connector is known such as from U.S. Pat. Nos. 3,945,114 and 3,491,426. Within forward and rearward ends of the tubing are located short sleeve-like preforms of fusible sealant material which will shrink and also tackify upon heating to bond and seal to the insulation of the wire, and to the cylindrical housing portions therewithin and to bond to the surrounding heat recoverable tubing; the termination is thus sealed.
Examples of such assemblies of heat recoverable tubing lengths with solder preforms and sealant preforms therein are disclosed in U.S Pat. Nos. 3,525,799; 4,341,921; 4,595,724 and 4,852,252. Similar assemblies and methods are disclosed in U.S. Pat. Applications Ser. No. 07/287,766 filed Dec. 21, 1988, Ser. No. 07/375,787 filed June 30, 1989, and Ser. No. 07/385,643 filed July 27, 1989 all assigned to the assignee hereof.
Another type of thermal energy generation is disclosed in U.S. Pat. No. 4,852,252 and in Ser. Nos. 07/287,766; 07/375,787 and 07/385,643: self-regulating temperature source technology is utilized wherein a bipartite metal foil is placed adjacent the termination site having the solder preform therearound, the foil having a first layer of low resistance nonmagnetic metal such as copper, and a second thin layer of high resistance metal having high magnetic permeability, such as a nickel/iron alloy, where the alloy has a property known as its Curie temperature. Such a bipartite metal foil will generate thermal energy when it has induced therein a constant amplitude high frequency alternating current such as radio frequency current which could be 13.56 MHz generated by an apparatus like that disclosed in U.S. Pat. No. 4,626,767; the heat will melt the solder and the sealant preforms and will shrink the tubing, simultaneously terminating the joint and sealing the termination; the temperature achieved in such a process will not exceed a certain known level, depending on the frequency and Curie temperature of the magnetic material used.
In Ser. No. 07/287,766 application of the requisite thermal energy to a pretermination assembly of a stripped wire end and a solder tail of a terminal both disposed inside a sleeve-like solder preform within a length of heat recoverable tubing, is accomplished by wrapping around the outside of the tubing a strip of foil having a layer of copper and a layer of nickel/iron alloy for example, and inducing a radio frequency current in the foil which then generates thermal energy; the thermal energy is transmitted to the tubing and the solder and sealant preforms, melting the solder to terminate the wire to the terminal and melting and tackifying the sealant preforms to bond to the insulated wire and terminal portions and shrinking the tubing. In one arrangement disclosed therein a plurality of terminations is performed simultaneously when a plurality of lengths of adjacent heat recoverable tubing around respective terminals and associated wire ends in a planar array is wrapped by a strip of foil which is then subjected to RF current such as by a coil of the RF current source or by electrodes of the source engaging ends of the foil, heating all the termination sites to the known temperature. In another disclosed arrangement, a single termination site has a strip of foil wrapped around the tubing, and the RF current is induced by a coil of the current source surrounding the foil.
It is desired to provide a means for soldering a single termination site in an array, enabling repair of a multiterminal connector.